It must have nothing to do with an ethical interpretation of the world. It must become cosmic and mystical, that is, it must seek to conceive all the devotion which rules in ethics as a manifestation of an inward, spiritual relation to the world. It must not go astray into abstract thinking, but must remain elemental, understanding self-devotion to the world to be self-devotion of human life to every form of living being with which it can come into relation. The origin of ethics is that I think out the full meaning of the world-affirmation which is given by nature together with the life-affirmation in my will-to-live, and try to make it a reality. To become ethical means to begin to think sincerely. Thinking is the agreement between willing and knowing which is come to within me. Its course is a naïve one, if the will demands of the knowledge to be shown a world which corresponds to the impulses which it carries within itself, and if the knowledge attempts to satisfy this requirement. The place of this dialogue, a dialogue which is doomed beforehand to produce no result, must be taken by a correct one, in which the will demands from the knowledge only what it really knows. [pg 245] If the knowledge answers solely with what it knows, it is always teaching the will one and the same fact, viz., that in and behind all phenomena there is will-to-live. Knowledge, though ever becoming deeper and more inclusive, can do nothing except take us deeper into the enigmatic fact that all that is, is will-to-live. Progress in science consists only in increasingly accurate description of the phenomena in which life in its innumerable forms appears and passes, letting us discover life where we did not previously expect it, and putting us in a position to turn to our own use in this or that way what we have learnt of the course of the will-to-live in nature. But what life is, no science can tell us. For our world- and life-view, then, the gain derived from knowledge is only that it makes it harder for us to be thoughtless, because it forces upon our attention ever more strongly the mystery of the will-to-live which we see stirring everywhere. Hence the difference between learned and unlearned is an entirely relative one. The unlearned man who, at the sight of a tree in flower, is overpowered by the mystery of the will-to-live which is stirring all round him, knows more truly than the learned one who studies under the microscope or in physical and chemical activity a thousand forms of the will-to-live, but who, with all his knowledge of the life-course of these manifestations of the will-to-live, is unmoved by the mystery that everything which exists is will-to-live, while he is puffed up with vanity at being able to describe exactly a fragment of the course of life.